Top 100 Contractors in PSC R405: Operations Research and Quantitative Analysis Services, FY2021

Name: Top 100 Contractors in PSC R405: Operations Research and Quantitative Analysis Services, FY2021
Creator: GovTribe

Parent companies by net contract obligations Oct 1, 2020 – Sep 30, 2021 Code page on GovTribe

The top 10 won 57% of FY2021 PSC R405 contract dollars

Contract obligations: $597,030,709 Net of deobligations, by contracts coded PSC R405
Contractors: 250 Parent companies with an obligation
Largest contractor: Leidos Holdings, Inc. $197 million, 31.3% of obligations
Data as of: Oct 14, 2026

Contract actions from FPDS (SAM.gov). How the rankings work · Download all 100 rows as CSV

Full ranking

Rank	Contractor	Net obligations	Share	Trend
1	Leidos Holdings, Inc. 4 awardees, including Leidos, Inc. Top agencies Army (Department of the Army) OSD (Office of the Secretary of Defense) DOJ (Department of Justice)	$196,838,922	31.3%	Rank history: #1 in FY2022, #1 in FY2023, #1 in FY2024 and #1 in FY2025; unchanged since FY2020.
2	Kbr, Inc. 3 awardees, including KBR Wyle Services, LLC Top agencies NASA (National Aeronautics and Space Administration) Navy (Department of the Navy)	$29,207,657	4.6%	Rank history: #2 in FY2022, #3 in FY2023, #47 in FY2024 and not on the FY2025 list; unchanged since FY2020.
3	Frontier Technology Inc. Top agencies DHA (Defense Health Agency)	$23,261,908	3.7%	Rank history: not on the FY2022–FY2025 lists; up 3 since FY2020.
4	Booz Allen Hamilton Holding Corporation 2 awardees, including Booz Allen Hamilton Inc. Top agencies VA (Department of Veterans Affairs) HHS (Department of Health and Human Services) DHS (Department of Homeland Security)	$19,974,656	3.2%	Rank history: #5 in FY2022, #4 in FY2023, #7 in FY2024 and #12 in FY2025; unchanged since FY2020.
5	Telesolv Consulting Inc. Top agencies DHS (Department of Homeland Security)	$16,792,677	2.7%	Rank history: #6 in FY2022, #13 in FY2023, #32 in FY2024 and not on the FY2025 list; up 3 since FY2020.
6	JP Systems, Inc. Top agencies VA (Department of Veterans Affairs)	$15,513,015	2.5%	Rank history: #23 in FY2022, #50 in FY2023, #55 in FY2024 and #15 in FY2025; up 3 since FY2020.
7	Changeis, Inc. Top agencies DOT (Department of Transportation)	$15,120,396	2.4%	Rank history: #7 in FY2022, #9 in FY2023, #13 in FY2024 and not on the FY2025 list; up 6 since FY2020.
8	Koniag, Inc. 2 awardees, including Koniag Services, Inc. and Eagle Harbor Solutions LLC Top agencies HHS (Department of Health and Human Services) DOS (Department of State)	$14,927,275	2.4%	Rank history: #8 in FY2022, #5 in FY2023 and not on the FY2024–FY2025 lists; up 11 since FY2020.
9	Deloitte LLP 2 awardees, including Deloitte & Touche LLP and Deloitte Consulting LLP Top agencies HHS (Department of Health and Human Services) DHS (Department of Homeland Security) DOT (Department of Transportation)	$13,447,050	2.1%	Rank history: #50 in FY2022, #31 in FY2023 and not on the FY2024–FY2025 lists; up 18 since FY2020.
10	Mckinsey & Company, Inc. Through Mckinsey & Company, Inc. Washington D.c. Top agencies VA (Department of Veterans Affairs)	$12,166,238	1.9%	Rank history: #3 in FY2022, #19 in FY2023 and not on the FY2024–FY2025 lists; new, not ranked in FY2020.
11	Reli Group Inc. Top agencies HHS (Department of Health and Human Services)	$10,368,722	1.7%	Rank history: #13 in FY2022, #15 in FY2023, #12 in FY2024 and #28 in FY2025; up 43 since FY2020.
12	American Systems Corporation Top agencies OSD (Office of the Secretary of Defense)	$10,235,236	1.6%	Rank history: #37 in FY2022, not on the FY2023–FY2024 lists and #9 in FY2025; up 3 since FY2020.
13	Personalis, Inc. Top agencies VA (Department of Veterans Affairs)	$9,747,936	1.6%	Rank history: not on the FY2022–FY2025 lists; down 10 since FY2020.
14	Accenture Federal Services LLC Top agencies HHS (Department of Health and Human Services)	$9,279,891	1.5%	Rank history: not on the FY2022–FY2025 lists; unchanged since FY2020.
15	It Concepts, Inc. Top agencies VA (Department of Veterans Affairs)	$8,725,333	1.4%	Rank history: not on the FY2022–FY2025 lists; up 155 since FY2020.
16	Premier Healthcare Solutions Inc. Top agencies HHS (Department of Health and Human Services)	$8,011,893	1.3%	Rank history: not on the FY2022–FY2025 lists; up 49 since FY2020.
17	The Cadmus Group LLC Top agencies EPA (Environmental Protection Agency) DOJ (Department of Justice)	$7,221,843	1.1%	Rank history: #14 in FY2022, #66 in FY2023 and not on the FY2024–FY2025 lists; down 6 since FY2020.
18	ABT Global LLC 2 awardees Top agencies HHS (Department of Health and Human Services)	$6,903,744	1.1%	Rank history: #39 in FY2022, #32 in FY2023 and not on the FY2024–FY2025 lists; up 6 since FY2020.
19	Fors Marsh Group LLC Top agencies DHRA (Defense Human Resources Activity) DHS (Department of Homeland Security)	$6,668,315	1.1%	Rank history: #18 in FY2022, #12 in FY2023, #38 in FY2024 and not on the FY2025 list; up 1 since FY2020.
20	Mathematica Inc 2 awardees Top agencies HHS (Department of Health and Human Services) DOL (Department of Labor) USDA (Department of Agriculture)	$6,542,609	1.0%	Rank history: #16 in FY2022, #46 in FY2023 and not on the FY2024–FY2025 lists; down 8 since FY2020.
21	Guidehouse Inc. 2 awardees Top agencies DHS (Department of Homeland Security)	$6,401,563	1.0%	Rank history: #12 in FY2022, #29 in FY2023, #43 in FY2024 and not on the FY2025 list; up 90 since FY2020.
22	Kapili Services, LLC Top agencies Army (Department of the Army)	$5,465,887	0.9%	Rank history: #32 in FY2022 and not on the FY2023–FY2025 lists; up 7 since FY2020.
23	Computational Physics, Inc. Top agencies Navy (Department of the Navy)	$5,420,092	0.9%	Rank history: #15 in FY2022, #17 in FY2023, #9 in FY2024 and #4 in FY2025; up 23 since FY2020.
24	Bennett Aerospace Inc. Top agencies DOJ (Department of Justice)	$5,409,806	0.9%	Rank history: not on the FY2022–FY2025 lists; down 3 since FY2020.
25	Exponent Inc. Top agencies DOS (Department of State) USDA (Department of Agriculture)	$4,826,890	0.8%	Rank history: #19 in FY2022, #23 in FY2023, #21 in FY2024 and not on the FY2025 list; up 38 since FY2020.
26	The Mitre Corporation Top agencies DHS (Department of Homeland Security) SSA (Social Security Administration)	$4,753,272	0.8%	Rank history: #26 in FY2022, #7 in FY2023, #4 in FY2024 and #67 in FY2025; up 29 since FY2020.
27	Northrop Grumman Corporation Through Northrop Grumman Systems Corporation Top agencies DFAS (Defense Finance and Accounting Service) Navy (Department of the Navy) DODEA (Department of Defense Education Activity)	$4,639,354	0.7%	Rank history: not on the FY2022–FY2025 lists; down 22 since FY2020.
28	Bluehalo LLC Top agencies USAF (Department of the Air Force)	$4,246,704	0.7%	Rank history: not on the FY2022–FY2025 lists; down 11 since FY2020.
29	Metaphase Consulting LLC Top agencies DHS (Department of Homeland Security)	$4,191,682	0.7%	Rank history: #11 in FY2022, #16 in FY2023, #24 in FY2024 and #45 in FY2025; new, not ranked in FY2020.
30	Jdsat, Inc. Top agencies Navy (Department of the Navy)	$3,984,686	0.6%	Rank history: #29 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
31	Tier TECH International, Inc. Top agencies DHS (Department of Homeland Security)	$3,888,847	0.6%	Rank history: #69 in FY2022, #95 in FY2023 and not on the FY2024–FY2025 lists; up 4 since FY2020.
32	The Boston Consulting Group Inc Through BCG Federal Corp. Top agencies DHA (Defense Health Agency)	$3,883,098	0.6%	Rank history: #28 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
33	Child Trends, Incorporated Top agencies HHS (Department of Health and Human Services)	$3,552,519	0.6%	Rank history: not on the FY2022 list, #47 in FY2023 and not on the FY2024–FY2025 lists; new, not ranked in FY2020.
34	Loch Harbour Group, Inc. Top agencies DHS (Department of Homeland Security)	$3,551,602	0.6%	Rank history: not on the FY2022–FY2025 lists; down 12 since FY2020.
35	Firebird Analytical Solutions & Technologies Inc. Top agencies DHS (Department of Homeland Security)	$3,532,955	0.6%	Rank history: #58 in FY2022, #38 in FY2023 and not on the FY2024–FY2025 lists; down 4 since FY2020.
36	Cherokee Insights LLC Top agencies USAF (Department of the Air Force)	$3,257,018	0.5%	Rank history: #33 in FY2022, #33 in FY2023, #30 in FY2024 and #32 in FY2025; new, not ranked in FY2020.
37	Human Resources Research Organization (Humrro) Top agencies Army (Department of the Army) USAF (Department of the Air Force)	$2,918,222	0.5%	Rank history: not on the FY2022–FY2024 lists and #2 in FY2025; down 7 since FY2020.
38	Toxcel LLC Top agencies DOT (Department of Transportation)	$2,917,374	0.5%	Rank history: not on the FY2022–FY2025 lists; up 28 since FY2020.
39	National Academy of Sciences Top agencies HHS (Department of Health and Human Services) Army (Department of the Army)	$2,871,252	0.5%	Rank history: not on the FY2022 list, #27 in FY2023, #78 in FY2024 and #77 in FY2025; down 16 since FY2020.
40	Linquest Corporation Through The Perduco Group, Inc. Top agencies USAF (Department of the Air Force) Navy (Department of the Navy)	$2,785,837	0.4%	Rank history: #52 in FY2022, #58 in FY2023, #87 in FY2024 and not on the FY2025 list; up 40 since FY2020.
41	Sofware LLC Top agencies USSOCOM (United States Special Operations Command)	$2,487,997	0.4%	Rank history: #36 in FY2022, #39 in FY2023 and not on the FY2024–FY2025 lists; up 10 since FY2020.
42	Tecolote Research, Inc. Top agencies DHS (Department of Homeland Security)	$2,427,761	0.4%	Rank history: #34 in FY2022, #51 in FY2023, #60 in FY2024 and #47 in FY2025; up 3 since FY2020.
43	GRA Inc. Top agencies DOT (Department of Transportation)	$2,413,962	0.4%	Rank history: #35 in FY2022 and not on the FY2023–FY2025 lists; up 9 since FY2020.
44	Westat, Inc. Top agencies USDA (Department of Agriculture)	$2,413,434	0.4%	Rank history: #92 in FY2022, #97 in FY2023, #22 in FY2024 and #53 in FY2025; up 3 since FY2020.
45	Kaihonua LLC Top agencies Army (Department of the Army) DHA (Defense Health Agency)	$2,397,204	0.4%	Rank history: #43 in FY2022, #76 in FY2023, #71 in FY2024 and #62 in FY2025; up 39 since FY2020.
46	Arttra Inc. Top agencies Army (Department of the Army)	$2,382,641	0.4%	Rank history: #61 in FY2022 and not on the FY2023–FY2025 lists; up 18 since FY2020.
47	Advanced Systems Technology & Management, Inc. Top agencies USAF (Department of the Air Force)	$2,342,573	0.4%	Rank history: #41 in FY2022, not on the FY2023 list, #49 in FY2024 and #58 in FY2025; up 2 since FY2020.
48	BDO USA LLP 2 awardees, including BDO Public Sector, LLC Top agencies VA (Department of Veterans Affairs)	$2,272,213	0.4%	Rank history: #40 in FY2022, #41 in FY2023, #48 in FY2024 and not on the FY2025 list; new, not ranked in FY2020.
49	Dunlap and Associates, Inc. Top agencies DOT (Department of Transportation)	$2,186,878	0.3%	Rank history: #85 in FY2022 and not on the FY2023–FY2025 lists; down 21 since FY2020.
50	Research Triangle Institute Top agencies HHS (Department of Health and Human Services)	$2,172,409	0.3%	Rank history: #21 in FY2022, not on the FY2023 list, #29 in FY2024 and #82 in FY2025; down 17 since FY2020.
51	James Bell Associates Inc. Top agencies HHS (Department of Health and Human Services)	$2,085,454	0.3%	Rank history: #48 in FY2022, #45 in FY2023 and not on the FY2024–FY2025 lists; down 13 since FY2020.
52	Group W Inc. Top agencies Army (Department of the Army)	$2,044,274	0.3%	Rank history: #42 in FY2022, #43 in FY2023, #42 in FY2024 and #49 in FY2025; down 2 since FY2020.
53	Fast-Track Drugs & Biologics, L.L.C. Top agencies HHS (Department of Health and Human Services)	$1,967,405	0.3%	Rank history: not on the FY2022–FY2023 lists, #16 in FY2024 and not on the FY2025 list; new, not ranked in FY2020.
54	Loyal Source Government Services LLC Top agencies Navy (Department of the Navy)	$1,959,774	0.3%	Rank history: not on the FY2022–FY2025 lists; down 1 since FY2020.
55	Netimpact Strategies Inc. Top agencies DHA (Defense Health Agency)	$1,917,889	0.3%	Rank history: #46 in FY2022 and not on the FY2023–FY2025 lists; up 2 since FY2020.
56	Axiom Resource Management, Inc. Top agencies USAF (Department of the Air Force)	$1,900,000	0.3%	Rank history: #51 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
57	Inalab Consulting, Inc. Top agencies Army (Department of the Army)	$1,805,326	0.3%	Rank history: #44 in FY2022, #42 in FY2023, #77 in FY2024 and not on the FY2025 list; up 29 since FY2020.
58	Agisol LLC Top agencies HHS (Department of Health and Human Services)	$1,499,408	0.2%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
59	Contracting Resources Group Inc. Top agencies DHA (Defense Health Agency)	$1,459,706	0.2%	Rank history: #53 in FY2022 and not on the FY2023–FY2025 lists; up 14 since FY2020.
60	Ernst & Young LLP Top agencies VA (Department of Veterans Affairs)	$1,449,307	0.2%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
61	David M. Dornbusch and Company Top agencies DOI (Department of the Interior)	$1,411,029	0.2%	Rank history: not on the FY2022–FY2025 lists; up 132 since FY2020.
62	Cacg, LLC Top agencies DISA (Defense Information Systems Agency)	$1,337,821	0.2%	Rank history: #81 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
63	Aleto, Inc. Top agencies DHA (Defense Health Agency)	$1,264,874	0.2%	Rank history: #67 in FY2022, #63 in FY2023, #68 in FY2024 and not on the FY2025 list; up 9 since FY2020.
64	Health Research and Analysis, LLC Top agencies HHS (Department of Health and Human Services)	$1,249,002	0.2%	Rank history: #75 in FY2022, #69 in FY2023, not on the FY2024 list and #74 in FY2025; up 14 since FY2020.
65	Aermor LLC Top agencies Navy (Department of the Navy)	$1,238,880	0.2%	Rank history: #47 in FY2022, #54 in FY2023, #66 in FY2024 and #61 in FY2025; up 11 since FY2020.
66	TMP Government LLC Top agencies OPM (Office of Personnel Management)	$1,196,357	0.2%	Rank history: #74 in FY2022, #40 in FY2023 and not on the FY2024–FY2025 lists; up 8 since FY2020.
67	Infotrend Incorporated Top agencies SEC (Securities and Exchange Commission)	$1,194,566	0.2%	Rank history: #68 in FY2022, #65 in FY2023, #84 in FY2024 and #72 in FY2025; up 4 since FY2020.
68	Nippon Telegraph and Telephone Corporation Through NTT Data Federal Services, Inc. Top agencies DOJ (Department of Justice)	$1,121,417	0.2%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
69	Mcneal Professional Services, Inc. Top agencies HHS (Department of Health and Human Services)	$1,085,203	0.2%	Rank history: #88 in FY2022 and not on the FY2023–FY2025 lists; down 13 since FY2020.
70	Metrics, LLC Top agencies VA (Department of Veterans Affairs)	$1,076,083	0.2%	Rank history: #73 in FY2022, #59 in FY2023 and not on the FY2024–FY2025 lists; new, not ranked in FY2020.
71	University of North Carolina at Chapel Hill Top agencies DOT (Department of Transportation) VA (Department of Veterans Affairs)	$994,009	0.2%	Rank history: not on the FY2022–FY2025 lists; up 46 since FY2020.
72	Insight Policy Research, Inc. Top agencies USDA (Department of Agriculture) DHRA (Defense Human Resources Activity)	$942,753	0.2%	Rank history: #65 in FY2022, #61 in FY2023 and not on the FY2024–FY2025 lists; up 11 since FY2020.
73	Cognitive Medical Systems, Inc. Top agencies VA (Department of Veterans Affairs)	$923,031	0.1%	Rank history: #25 in FY2022, #86 in FY2023 and not on the FY2024–FY2025 lists; up 177 since FY2020.
74	DCI Consulting Group Inc. Top agencies DOJ (Department of Justice)	$903,905	0.1%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
75	Altarum Institute Through Palladian Partners, Inc. Top agencies HHS (Department of Health and Human Services)	$901,361	0.1%	Rank history: #100 in FY2022 and not on the FY2023–FY2025 lists; up 14 since FY2020.
76	The Manhattan Strategy Group LLC Top agencies DOL (Department of Labor)	$875,076	0.1%	Rank history: #64 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
77	Athena Technology Group, Inc. Top agencies VA (Department of Veterans Affairs)	$853,205	0.1%	Rank history: #86 in FY2022 and not on the FY2023–FY2025 lists; up 22 since FY2020.
78	ICF Esac, LLC Top agencies VA (Department of Veterans Affairs)	$850,880	0.1%	Rank history: not on the FY2022–FY2025 lists; up 13 since FY2020.
79	Totally Joined for Achieving Collaborative Techniques (Tjfact), LLC Top agencies Army (Department of the Army)	$848,400	0.1%	Rank history: #83 in FY2022, #87 in FY2023, #86 in FY2024 and #79 in FY2025; new, not ranked in FY2020.
80	General Dynamics Information Technology, Inc. Top agencies USTRANSCOM (Department of Defense United States Transportation Command)	$798,755	0.1%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
81	Quantics Incorporated Top agencies Navy (Department of the Navy)	$741,293	0.1%	Rank history: #87 in FY2022, #82 in FY2023 and not on the FY2024–FY2025 lists; up 15 since FY2020.
82	Claxton Logistics Services LLC Top agencies Army (Department of the Army)	$709,976	0.1%	Rank history: #90 in FY2022, #88 in FY2023, #85 in FY2024 and #84 in FY2025; up 13 since FY2020.
83	C5T Corporation Top agencies USTRANSCOM (Department of Defense United States Transportation Command)	$676,195	0.1%	Rank history: #63 in FY2022, #60 in FY2023, not on the FY2024 list and #57 in FY2025; new, not ranked in FY2020.
84	National Opinion Research Center Top agencies HHS (Department of Health and Human Services) DOT (Department of Transportation)	$657,602	0.1%	Rank history: #22 in FY2022, #49 in FY2023, not on the FY2024 list and #23 in FY2025; down 50 since FY2020.
85	Oil Price Information Service LLC Through IHS Global Inc. Top agencies HHS (Department of Health and Human Services)	$650,288	0.1%	Rank history: #62 in FY2022, #78 in FY2023 and not on the FY2024–FY2025 lists; up 12 since FY2020.
86	Solutions for Information Design, Inc. Top agencies DHS (Department of Homeland Security)	$626,683	0.1%	Rank history: #91 in FY2022, #90 in FY2023, not on the FY2024 list and #66 in FY2025; up 18 since FY2020.
87	VT Milcom Inc. Top agencies USAF (Department of the Air Force)	$605,000	0.1%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
88	George Mason University Top agencies Navy (Department of the Navy)	$577,415	0.1%	Rank history: not on the FY2022–FY2025 lists; up 34 since FY2020.
89	Analyticx LLC Top agencies DOS (Department of State)	$550,000	0.1%	Rank history: #99 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
90	American Institutes for Research In the Behavioral Sciences Top agencies IMLS (The Institute of Museum and Library Services)	$537,000	0.1%	Rank history: #56 in FY2022, #64 in FY2023, #11 in FY2024 and #8 in FY2025; down 13 since FY2020.
91	Tria Federal, LLC Top agencies VA (Department of Veterans Affairs)	$503,586	0.1%	Rank history: not on the FY2022–FY2025 lists; down 12 since FY2020.
92	Aegis Aerospace Inc. Top agencies USAF (Department of the Air Force)	$499,610	0.1%	Rank history: not on the FY2022–FY2025 lists; down 50 since FY2020.
93	Bering Straits Native Corporation Through Bering Global Solutions, LLC Top agencies USAF (Department of the Air Force)	$487,728	0.1%	Rank history: #95 in FY2022 and not on the FY2023–FY2025 lists; down 52 since FY2020.
94	ICF International, Inc. 2 awardees, including ICF Incorporated, L.L.C. Top agencies HHS (Department of Health and Human Services) USDA (Department of Agriculture)	$476,969	0.1%	Rank history: #30 in FY2022, #48 in FY2023 and not on the FY2024–FY2025 lists; down 68 since FY2020.
95	BDR Solutions, LLC Top agencies VA (Department of Veterans Affairs)	$455,694	0.1%	Rank history: #97 in FY2022, #96 in FY2023 and not on the FY2024–FY2025 lists; up 10 since FY2020.
96	Interface Media Group Inc. Top agencies DOS (Department of State)	$451,240	0.1%	Rank history: not on the FY2022–FY2025 lists; new, not ranked in FY2020.
97	Compagnie Merieux Alliance Through Advanced Bioscience Laboratories, Inc. Top agencies HHS (Department of Health and Human Services)	$450,000	0.1%	Rank history: not on the FY2022 list, #91 in FY2023 and not on the FY2024–FY2025 lists; up 27 since FY2020.
98	Vysnova Partners, LLC Top agencies USAF (Department of the Air Force)	$448,145	0.1%	Rank history: #96 in FY2022 and not on the FY2023–FY2025 lists; new, not ranked in FY2020.
99	Optimal Solutions Group, L.l.c Top agencies SBA (Small Business Administration)	$446,655	0.1%	Rank history: #77 in FY2022, #89 in FY2023 and not on the FY2024–FY2025 lists; down 18 since FY2020.
100	Oregon Health & Science University Top agencies VA (Department of Veterans Affairs)	$436,549	0.1%	Rank history: #98 in FY2022, #81 in FY2023 and not on the FY2024–FY2025 lists; up 15 since FY2020.

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100 of 250 contractors listed here. See the rest on GovTribe.

How this ranking works

Source: every contract action FPDS records (as published on SAM.gov) in the period, as GovTribe received it.
Amounts are net obligations: what was obligated, less what was deobligated. Shares are of $628 million obligated before deobligations, so they never pass 100%.
Parent companies: each action counts under the ultimate parent its award record names, or under the awardee when it names none, so no dollar counts twice. Parents of the same name (Inc., LLC and the like aside) count as one company, since FPDS records a company's parent under more than one UEI over time. GovTribe corrects a few parents and names by hand; see the corrections.
Fiscal year 2021 ran Oct 1, 2020 – Sep 30, 2021. The Department of Defense reports its contract actions to FPDS about 90 days late, so a fiscal year is ranked once they're in, in February, and the list doesn't change after.
Rank changes compare with FY2020. "New" marks a company outside that period's top 500, and "Returned" one of those that was on an earlier fiscal year's list.
Rank lines show each company's rank on every fiscal year's list since FY2021, #1 at the top, on a scale that gives the top of the list more room. A dashed stretch spans years it wasn't on the list. The step from FY2020 takes the color of the rank change beside it.
Placeholder recipients FPDS uses when it names no company ("Miscellaneous Foreign Contractors" and the like) aren't ranked.

Quick answers

Who were the top 10 PSC R405 contractors in FY2021?

1. Leidos Holdings, Inc. ($197M), 2. Kbr, Inc. ($29.2M), 3. Frontier Technology Inc. ($23.3M), 4. Booz Allen Hamilton Holding Corporation ($20M), 5. Telesolv Consulting Inc. ($16.8M), 6. JP Systems, Inc. ($15.5M), 7. Changeis, Inc. ($15.1M), 8. Koniag, Inc. ($14.9M), 9. Deloitte LLP ($13.4M), 10. Mckinsey & Company, Inc. ($12.2M).

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